Transcript for Trump fires secretary of state on Twitter after months of clashes

the storm swirling inside president trump's cabinet. President trump firing secretary of state Rex tillerson, and doing so in a tweet. The president firing tillerson, then calling them several hours later from air force one. The president naming CIA director Mike Pompeo as the new secretary of state. And look at the wall tonight. At the top there, tillerson fired. He wasn't the only one fired today. The undersecretary of state Steve Goldstein, who tweeted that tillerson did not know that the firing was coming, he was fired, too. In addition to the van caseys that exist at the top of the state department. So, we begin tonight with ABC's white house correspondent Jonathan Karl. Reporter: President trump is in California today, reviewing prototypes of the border wall he hopes to build. A trip overshadowed by what he did early this morning, firing his secretary of state, on Twitter, no less. "Mike Pompeo, director of the CIA, will become our new secretary of state," the president declared. "Thank you to Rex tillerson for his service!" As he left the white house, the president explained he just didn't see eye-to-eye with his secretary of state. Rex and I have been talking about this for a long time. We got along actually quite well but we disagreed on things. Reporter: As for his new choice for top diplomat? Tremendous energy, tremendous intellect. We're always on the same wave length. Reporter: Tillerson's day began flying back from Africa, landing in Washington at 4:00 A.M. At 8:44, seeing the tweet that the president had fired him. And minutes after that, his spokesman putting out a statement saying tillerson had wanted to stay on the job, adding, "The secretary did not speak to the president and is unaware of the reason for the firing, but he is grateful for the opportunity to serve." Shortly after that, tillerson's spokesman was fired, too, and a dejected tiller sob sa ertillerson said the did, eventually, come from the president, hours after he was fired. I received a call today from the president of the united States a little after noontime from air force one. Reporter: The timing of the firing was a shock, but it's no secret the president has clashed with his secretary of state for months. On the Iran nuclear deal, on the Paris climate agreement and, most dramatically, on north Korea. Tillerson was blindsided by the president's hasty decision to agree to meet with Kim Jong-un, telling reporters hours earlier -- We're a long ways from negotiations. Reporter: And in October, trump publicly mocked tillerson for suggesting talks with North Korea, saying tillerson was, quote, "Wasting his time trying to negotiate with little rocket man." And last summer, tillerson reportedly called the president a moron, and then refused to deny making the comment. I'm not going to deal with petty stuff like that. Reporter: That prompted trump to call tillerson weak. Sometimes I'd like him to be a little bit tougher, but other than that, we have a very good relationship. Reporter: And the president even suggested, quote, "I guess we'll have to compare iq tests. And I can tell you who is going to win." Adding to all the drama, the president today hinted there may be more firings to come. I'm really at a point where we're getting very close to having the cabinet and other things that I want. So, let's get to Jon Karl with us live tonight from the white house. And Jon, as you know, tillerson today did not mention president trump by name other than mentioning that phone call from air force one. But he did urge state department officials to move forward with, quote, honesty and integrity, were the words he chose today. There's another shakeup to get to tonight, after the departures of hope hicks, rob porter, a third aide, you've learned, escorted out of the white house? Reporter: This was one of the very few originals left, David. John Mcentee, the president's personal assistant, or body man, seen at his side virtually every day on all of those trips, late yesterday, he was escorted off the white house grounds, not even allowed to pack up his desk or to go and retrieve his jacket. We're told it was problems with his security clearance. But David, just minutes after news of his firing broke, we learned that he's been hired to work at the trump re-election campaign. All right, Jon Karl with us live tonight. Jon, thank you. With those vacancies at the west wing and the state don't tonight, we do have one question tonight. We go to Martha Raddatz. Martha, you covered the state department for years. Let's look at that list of vacancies we showed at the top here. The two new firings and then all the vacancies that exist. Have you seen the this? Reporter: It's a ghosttown. There is no confirmed assistant for east Asia, no ambassador for South Korea and no special representative from North Korea policy. He left just before the meeting was announced, so, all of the key people at state responsible for the region are in acting or interim positions. But maybe Mike Pompeo can change all of that. Speaking of Mike Pompeo, the choice to succeed him to run the CIA will be Gina Haspel, the first woman to run the spy agency. Reporter: Gina Haspel was in charge of one of the CIA black sites where they did so-called enhanced interrogation, including waterboarding of Al Qaeda operatives Abu sa bayda. She is no doubt going to be asked about that during con for make hearings. David? Martha Raddatz, thank you. Also at this hour, the

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